The invention is based on a hydraulic high-pressure pump for motor vehicle brake systems.
A high-pressure pump of this kind having a pump element is already known (German Offenlegungsschrift 39 07 969) U.S. Pat. No. 4,988,147, the cylinder of which has a solid valve housing on the side of the outlet valve. The ball of outlet valve and a helical compression spring that engages the ball are received in the valve housing. The cylinder with the outlet valve and valve housing forms an assembly unit that is inserted into a bore of the pump housing and is supported on a step of the bore by a collar of the cylinder. A disk-shaped closure element that is seated on the valve housing is fitted tightly into the pump housing bore, which is widened in the region of the valve housing. A damper chamber, which communicates with the outlet valve and from which a throttle bore of the pump housing begins, extends around the valve housing between the bore step and the closure element. A closure screw threaded into the pump housing bore fixes not only the cylinder with the valve housing but also the closure element.
This known embodiment of the high-pressure pump is of time-tested construction. Because of the valve housing, which is required to receive the helical compression spring and the valve ball and also to hold down the cylinder in the pump housing, the pump element has a certain structural length, which necessitates a correspondingly large installation space in the pump housing. Moreover, the increased volumetric requirement is also dictated by the embodiment of the damper chamber in the form of an annular chamber and by the fixation of the pump element and closure element with the closure screw.